Is Marijuana Safe?
Breathing In the Smoke
Marijuana smoke is also filled with many of the same chemicals as tobacco smoke, including ammonia, hydrogen cyanide, and formaldehyde. Some of these chemicals are known to cause cancer. Most users smoke pot in a joint or water pipe, so they breathe the smoke straight into their lungs.
There's no proof that smoking marijuana causes lung cancer like cigarettes do. But people who smoke pot do show signs of damage and precancerous changes in their lungs, especially if they also smoke cigarettes. And a study published in 2013 in Cancer Causes & Control found that heavy marijuana smoking might raise the risk of lung cancer.
Marijuana on the Brain
Could smoking marijuana change the way the brain works? That's what researchers are finding.
•Brain imaging scans of heavy marijuana smokers have revealed changes in blood flow to parts of the brain involved in memory and attention. Researchers have also noted differences in the size and shape of the thalamus, the part of the brain that's involved in consciousness and information processing.
•Heavy pot smokers in studies score lower than non-users on tests of memory, attention, and learning. The more they smoked, the worse they did.
•The effects of smoking pot may be even more pronounced in teenage smokers than adults, because teens' brains are still developing.
•Regular users are more likely to be diagnosed with schizophrenia, especially when they have a family history of the condition.
Other Health Effects
Marijuana can have effects beyond the lungs and brain. These include:
•Fast heart rate
•Increased risk of heart attack (within the first hour after smoking)
•Suicidal thoughts in teens
Is It Addictive?
People who stop smoking pot don't have the same withdrawal symptoms -- like anxiety and sweating -- they'd get if they were addicted to a drug like heroin. Yet those who use marijuana all the time can have a hard time stopping.
The condition of marijuana dependence does exist, studies show. Some long-term, near-daily users seek treatment to quit, yet they keep smoking marijuana, despite its social, psychological, and physical effects. They also mention effects such as relationship and family problems, low energy and self-esteem, memory problems, and low life-satisfaction.
Marijuana can also lead to other addictions¸ especially in people who start smoking at a young age. That's why it's sometimes called a "gateway drug." One study found that young people who smoke marijuana are more likely to abuse other drugs, including prescription opioids, in the future.
Eat It Instead?
Although smoking is the most common way to use marijuana, some people bake it into a brownie or other food. Eating pot might spare you the lung effects of this drug, but that doesn't mean it's safe.